Effects of Power-Endurance and Controlled Heavy Squat Protocols on Vertical Jump Performance in Females

The purpose of this investigation was to examine the immediate and acute vertical jump performance responses throughout and following two different free-weight back squat exercise protocols. Fifteen resistance-trained women (mean ± SD: age = 21.8 ± 0.9 years; height = 164.6 ± 8.4 cm; mass = 68.5 ± 9.2 kg) performed vertical jumps before (Pre), immediately after each set (S1-S5), and up to 20 minutes post squat exercise (Post0-Post20) of either a power-endurance (PE; 5×16 at 40% 1-RM) or controlled heavy (CHP; 5×8 at 80%) protocol. Participants' jump height (JH), mean (MP), peak power (PP), mean (MV) and peak velocity (PV) were measured using a linear position transducer. 2-way repeated measures ANOVAs were run for all dependent variables. In the case of the violation of sphericity Greenhouse-Geisser results were reported. No significant intensity × time interactions were observed for any of the variables (p = 0.30-0.87). Main effects for time were observed (p ≤ 0.001, ηp² = 0.52) for MP and MV, which were significantly lower than Pre at S2 through S5-Post0 (p = 0.001-0.02) time points. Additionally, main effects for time were observed (p ≤ 0.001, ηp² = 0.43) for PP and PV, which were significantly lower than Pre at all time points (p = 0.001-0.03) with the exception of Post10 (p = 0.17-0.21). Lastly, JH was significantly lower than Pre for all time points (p ≤ 0.001-0.02) except for Post5 (p = 0.13) and Post10 (p = 0.25). This study suggests overall training volume and not training-load could have attributed to the similar fatigue and recovery-related responses that were observed. The present findings suggest that vertical jump performance may be negatively affected following moderate to heavy exercise for up to 20 minutes.